Personalized Mechanical Eggineer Toddler Long Sleeve T-Shirt. Eggineers are engineering eggheads and this egg with gears in hand and on it's hard hat with mechanical eggineer text, is a humorous design to tickle your mechanical engineer's funny bone at birthdays, holidays and graduation. A classic for Fall, Winter and Spring, these long sleeve toddler t-shirts are sure to be a staple in your child's wardrobe. Whether layered or alone, this t-shirt is soft yet durable enough to stand up to your toddler's playtime demands.